1. Field of the Invention
The present invention relates to a method of manufacturing a silicon carbide single crystal and a silicon carbide single crystal substrate.
2. Description of the Background Art
Use of silicon carbide (SiC) as a semiconductor material has actively been studied in recent years. Wide band gap of SiC can contribute to enhancement of performance of a semiconductor device. In manufacturing an SiC semiconductor, normally, an SiC substrate is required. An SiC substrate (wafer) can be formed by slicing an SiC single crystal (ingot).
Japanese Patent Laying-Open No. 2001-294499 (Patent Document 1) discloses a silicon carbide single crystal wafer having a diameter not smaller than 50 mm and used for a substrate for growing an epitaxial thin film. According to this publication, deviation in orientation of a growth surface between any two points in a wafer plane can be not more than 60 seconds/cm and thereby a thin film of good quality can epitaxially be grown on the entire surface of the wafer.
According to the studies conducted by the present inventors, simply by controlling deviation in orientation of the growth surface of the silicon carbide single crystal substrate as in the technique in Japanese Patent Laying-Open No. 2001-294499, variation in manufacturing of a semiconductor device manufactured with this silicon carbide substrate could not sufficiently be lessened.